Leaders from both the United States and Great Britain said Thursday that they were exploring the possibility that a bomb brought down a Russian airliner over Egypt's Sinai Peninsula, killing all 224 aboard.

US President Barack Obama told a US radio station Thursday that a bomb could have taken down the Russian airliner, while admitting it was too early to be certain.

"I think there is a possibility that there was a bomb on board, and we are taking that very seriously," he said.

In London, British Prime Minister David Cameron told reporters that the destruction of the airliner could have been intentional.

"We cannot be certain that the Russian airliner was brought down by a terrorist bomb, but it looks increasingly likely that that was the case," Cameron said.

He made his comments as he was hosting Egyptian President Abdel-Fattah el-Sissi, whose government has avoided drawing any conclusions.

The so-called "Islamic State" jihadist group has claimed responsibility for the October 31 disaster, in which the Saint Petersburg-bound jet crashed after taking off from Sharm el-Sheikh airport.

Russia discounts bomb theory

Russia has continued to downplay the bombing scenario, saying it was too early to draw conclusions over the fate of the Airbus A321 jet that broke up mid-air at cruising altitude of 30,000 feet about 23 minutes after takeoff.

Russian government spokesman Dmitry Peskov said the cause of the destruction of Flight KGL9268 is still uncertain.

"Theories about what happened and the causes of the incident can only be pronounced by the investigation," Peskov said.

Several European countries including Germany, Ireland and the Netherlands have suspended flights to and from Sharm al-Sheikh, leaving tens of thousands of tourists stranded in the Red Sea resort.

Britain has said flights from Sharm el-Sheikh to London will resume on Friday but added passengers will travel only with hand luggage.

"These flights will operate under special security measures mandated by the UK government," a statement from Thomson Airways said.

Russian commercial flights have also continued to operate.

If claims by Islamic State that it brought down the civilian airliner prove to be true, it would be a first for the militant group that controls swathes of Syria and Iraq.

It would also likely devastate Egypt's tourism industry, which has been striving to recover since the Arab Spring revolution and subsequent military coup that brought el-Sissi to power in 2013.

jar/sms (Reuters, AFP)